Prepare to have your mind blown.
The law is this: every odd-numbered Star Trek movie is dreck. Every even-numbered Star Trek movie is terrific. This Law - the subjectivity of movie criticism notwithstanding - held up perfectly for decades.
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We are bound to accept all 21 ecumenical councils as valid and binding. Mind you, some disciplinary rulings of historical councils are no longer binding, but their doctrinal teachings certainly are.
(For example, the Council of Nicaea forbid kneeling on Sundays…while this is still the practice in the East, the Latin West obviously is no longer bound by this discipline…yet we are certainly bound by the Council’s dogmatic teachings concerning the divinity of Christ).

I am assuming you mean General/Ecumenical Councils. The question doesn’t really make sense as Councils do a lot of things. It’s like asking which Popes are you bound to believe–Popes do and say lots of things. Like Popes, Councils legislate, they make definitive dogmatic judgments, they provide pastoral guidance, they address issues relevant to time and place, they make political statements, etc., etc.

Because a Council exercises the supreme authority in the Church, we must receive its particular acts as the Council intends.

That being said Catholics aren’t required to go back and study all the prior Councils. The ordinary, living Magisterium, generally suffices. For example, no one needs to go back and study the Second Council of Nicea to know the Catholic Church teaches it is ok to venerate images.

We are bound to submit to the dogmatic definitions of all the ecumenical councils and those of the Popes. If you do not and, after having been admonished at least twice you continue not to, then you’re a heretic.